fix: synchronous reorder for keywords and sites (v0.3.0)

app/src/main/java/com/hotdeal/alarm/presentation/main/MainViewModel.kt

@@ -109,11 +109,13 @@ class MainViewModel @Inject constructor(
     }
 
     fun reorderSites(fromIndex: Int, toIndex: Int) {
-        viewModelScope.launch {
-            val current = siteOrder.value.toMutableList()
-            if (fromIndex in current.indices && toIndex in current.indices) {
-                val item = current.removeAt(fromIndex)
-                current.add(toIndex, item)
+        // siteOrder는 appSettings.siteOrder에서 stateIn으로 가져오므로
+        // appSettings를 즉시 저장하고 Flow가 업데이트되도록 함
+        val current = siteOrder.value.toMutableList()
+        if (fromIndex in current.indices && toIndex in current.indices) {
+            val item = current.removeAt(fromIndex)
+            current.add(toIndex, item)
+            viewModelScope.launch {
                 appSettings.setSiteOrder(current)
             }
         }
@@ -128,7 +130,6 @@ class MainViewModel @Inject constructor(
                     isEnabled = true
                 )
             )
-            // 키워드 순서 맨 앞에 추가
             val currentOrder = appSettings.keywordOrder.first().toMutableList()
             currentOrder.add(0, newId)
             appSettings.setKeywordOrder(currentOrder)
@@ -151,12 +152,16 @@ class MainViewModel @Inject constructor(
     }
 
     fun reorderKeywords(fromIndex: Int, toIndex: Int) {
-        val state = uiState.value as? MainUiState.Success ?: return
-        viewModelScope.launch {
-            val current = state.keywords.toMutableList()
-            if (fromIndex in current.indices && toIndex in current.indices) {
-                val item = current.removeAt(fromIndex)
-                current.add(toIndex, item)
+        // uiState를 동기적으로 즉시 업데이트하여 빠른 드래그 시 stale 데이터 방지
+        val state = _uiState.value as? MainUiState.Success ?: return
+        val current = state.keywords.toMutableList()
+        if (fromIndex in current.indices && toIndex in current.indices) {
+            val item = current.removeAt(fromIndex)
+            current.add(toIndex, item)
+            // UI 즉시 갱신
+            _uiState.value = state.copy(keywords = current)
+            // DataStore 비동기 영속화
+            viewModelScope.launch {
                 appSettings.setKeywordOrder(current.map { it.id })
             }
         }